Leakage Characteristic Analysis And Structure Optimization Of Hydraulic Slide Valve

The application of hydraulic spool valve is more and more extensive,and its performance requirements are getting higher and higher.As a leakage problem that affects the safety and stability of the spool valve,it cannot be ignored.Since there is a certain annular gap between the valve body and the spool of the hydraulic spool valve,the flow of the medium in the annular gap has a great influence on the leakage of the spool valve.If the leakage is too large,the movement speed of the spool will be reduced,and the movement speed of the spool will be reduced.The energy loss of the whole machine seriously affects the safety and stability of the valve.This paper studies the flow characteristics in the fitting clearance of the valve body and spool,optimizes and improves the structural parameters of the hydraulic spool valve body and spool,and deeply explores the influence of influencing factors on the leakage.The main research contents of this paper are as follows:(1)Based on the theoretical analysis of hydraulic spool valve leakage,considering the deformation,eccentricity and tilt of the spool,a leakage model suitable for the valve body and spool fit clearance is established.The influencing factors of the leakage in the mathematical model are discussed,and the AMESim hydraulic simulation is established.The system analyzes the influence law of fit clearance,spool diameter,and working pressure on leakage.(2)In view of the high oil temperature and the large pressure difference between the two ends of the fitting gap,a one-way thermo-fluid-solid coupling simulation system was built based on ANSYS-Workbench software,and the deformation distribution of the valve body and spool was analyzed,and the minimum fitting gap was obtained by calculation.Explored the influence of valve port opening,balance groove and taper on the flow field characteristics of hydraulic spool valve,and optimized the structural size of the hydraulic spool valve body and spool based on the MATLAB genetic algorithm toolbox,and compared the pre-optimized and The size of the leakage of the hydraulic spool valve after optimization.(3)Based on the CFD simulation software,the multiphase flow simulation analysis was carried out,the distribution characteristics of the flow field in the hydraulic slide valve when the pollutant particles were contained were explored,and the influence of the change of the pollutant particle concentration on the leakage was analyzed.At the same time,the oil temperature was studied,considering the influence of the oil temperature increase on the oil viscosity,the influence of temperature on the leakage was further explored.Orthogonal analysis was carried out by integrating the main influencing factors,and the sensitivity of the influencing factors to leakage was studied.(4)According to the optimized results,the hydraulic spool valve is designed,and the multi-functional hydraulic test bench is used to test the optimized hydraulic spool valve before and after the optimization.By controlling the pressure difference,flow and temperature,the leakage under different working conditions is measured.The law of leakage with pressure difference and temperature was obtained,and the leakage of hydraulic slide valve before and after optimization was compared and analyzed.